Card edge connector equipped with solder balls on contacts

Abstract

A card edge connector includes an insulative elongated housing, two rows of contacts disposed in the housing. The housing includes a pair of side walls extending along the longitudinal direction with a receiving slot therebetween in a transverse direction perpendicular to the longitudinal direction. The receiving slot is configured to receive a card type memory module. Each contact is equipped with the solder ball for surface mounting upon the printed circuit board. The contact includes a retaining section secured to the housing, a deflectable contacting section extending upwardly from the retaining section, and a tail section extending downwardly from the retaining section and including a connecting section and a solder pad. The solder pads of the contacts in a same row along the longitudinal direction are alternately arranged in opposite directions in the transverse direction perpendicular to the longitudinal direction.

What is claimed is: 
     
       1. An electrical connector for receiving a memory module, comprising:
 an insulative elongated housing having a pair of elongated side walls extending along a longitudinal direction with a receiving slot formed therebetween in a transverse direction perpendicular to the longitudinal direction; 
 two rows of the passageways formed in the corresponding side walls, respectively; 
 two rows of contacts retained in the pair of side walls, respectively, and having corresponding contacting regions exposed in the receiving slot; and 
 each of said contacts including a retaining section retained in the corresponding passageway, a resilient contacting section extending upwardly from the retaining section and into the receiving slot, and a tail section extending downwardly from the retaining section and including a connecting section linked to the retaining section and a horizontal solder pad at a bottom, the solder pads being categorized with inward solder pads extending toward the receiving slot, and outward solder pads extending away from the receiving slot; wherein 
 the contacts in a same row are paired for every two neighboring contacts so as to form a plurality of pairs, each pair have either the corresponding inward solder pads or the corresponding outward solder pads, and the pairs having the corresponding inward solder pads and the pairs having the corresponding outward solder pads are alternately arranged with each other in a staggered manner along the longitudinal direction; wherein 
 in each pair, a distance between centerlines of the solder pads is larger than that between centerlines of the retaining sections. 
 
     
     
       2. The electrical connector as claimed in  claim 1 , wherein a dimension of the solder pad is larger than that of the connecting section in the longitudinal direction. 
     
     
       3. The electrical connector as claimed in  claim 1 , wherein each of said solder pad has a widened section which extends along the longitudinal direction only on one side thereof. 
     
     
       4. The electrical connector as claimed in  claim 1 , wherein in each pair, a distance between centerlines of the connecting sections and larger than that between the centerlines of the retaining sections in the longitudinal direction. 
     
     
       5. The electrical connector as claimed in  claim 1 , wherein the contacts aligned with each other in the transverse direction, have the corresponding solder pads of which one is the inward solder pad and the other is the outward solder pad. 
     
     
       6. The electrical connector as claimed in  claim 1 , wherein the contacts aligned with each other in the transverse direction, have the corresponding solder pads both being either the inward solder pads or the outward solder pads. 
     
     
       7. The electrical connector as claimed in  claim 1 , wherein the neighboring inward solder pad and outward solder pad are partially overlapped with each other in the transverse direction. 
     
     
       8. The electrical connector as claimed in  claim 1 , wherein each of said solder pads is equipped with a solder ball. 
     
     
       9. The electrical connector as claimed in  claim 1 , wherein the contacting aligned with each other in the transverse direction, have the corresponding solder pads aligned with each other in the transverse direction. 
     
     
       10. An electrical connector for receiving a memory module, comprising:
 an insulative elongated housing having a pair of elongated side walls extending along a longitudinal direction with a receiving slot formed therebetween in a transverse direction perpendicular to the longitudinal direction; 
 two rows of the passageways formed in the corresponding side walls, respectively; 
 two rows of contacts retained in the pair of side walls, respectively, and having corresponding contacting regions exposed in the receiving slot; and 
 each of said contacts including a retaining section retained in the corresponding passageway, a resilient contacting section extending upwardly from the retaining section and into the receiving slot, and a tail section extending downwardly from the retaining section and including a connecting section linked to the retaining section and a horizontal solder pad at a bottom, the solder pads being categorized with inward solder pads extending toward the receiving slot, and outward solder pads extending away from the receiving slot; wherein 
 the contacts in a same row are paired for every two neighboring contacts so as to form a plurality of pairs, each pair have either the corresponding inward solder pads or the corresponding outward solder pads, and the pairs having the corresponding inward solder pads and the pairs having the corresponding outward solder pads are alternately arranged with each other in a staggered manner along the longitudinal direction; wherein 
 in each pair, a distance between centerlines of the solder pads is larger than a pitch of the passageways along the longitudinal direction. 
 
     
     
       11. The electrical connector as claimed in  claim 10 , wherein a dimension of the solder pad is larger than that of the connecting section in the longitudinal direction. 
     
     
       12. The electrical connector as claimed in  claim 10 , wherein each of said solder pad has a widened section which extends along the longitudinal direction only on one side thereof. 
     
     
       13. The electrical connector as claimed in  claim 10 , wherein in each pair, a distance between centerlines of the connecting sections and larger than that between the centerlines of the retaining sections in the longitudinal direction. 
     
     
       14. The electrical connector as claimed in  claim 10 , wherein the contacts aligned with each other in the transverse direction, have the corresponding solder pads of which one is the inward solder pad and the other is the outward solder pad. 
     
     
       15. The electrical connector as claimed in  claim 10 , wherein the contacts aligned with each other in the transverse direction, have the corresponding solder pads both being either the inward solder pads or the outward solder pads. 
     
     
       16. The electrical connector as claimed in  claim 10 , wherein the neighboring inward solder pad and outward solder pad are partially overlapped with each other in the transverse direction. 
     
     
       17. The electrical connector as claimed in  claim 10 , wherein each of said solder pads is equipped with a solder ball. 
     
     
       18. The electrical connector as claimed in  claim 10 , wherein the contacting aligned with each other in the transverse direction, have the corresponding solder pads aligned with each other in the transverse direction. 
     
     
       19. An electrical connector for receiving a card type memory module, comprising:
 an insulative elongated housing having a pair of elongated side walls extending along a longitudinal direction with a receiving slot formed therebetween in a transverse direction perpendicular to the longitudinal direction; 
 two rows of the passageways formed in the corresponding side walls, respectively; 
 two rows of contacts retained in the pair of side walls, respectively, and having corresponding contacting regions exposed in the receiving slot; and 
 each of said contacts including a retaining section retained in the corresponding passageway, a resilient contacting section extending upwardly from the retaining section and into the receiving slot, and a tail section extending downwardly from the retaining section and including a connecting section linked to the retaining section and a horizontal solder pad at a bottom; wherein 
 the contacts in a same row are paired for every two neighboring contacts so as to form a plurality of pairs, each pair have either the corresponding inward solder pads or the corresponding outward solder pads, and the pairs having the corresponding inward solder pads and the pairs having the corresponding outward solder pads are alternately arranged with each other in a staggered manner along the longitudinal direction; 
 each of said solder pads is equipped with a solder ball thereunder. 
 
     
     
       20. The electrical connector as claimed in  claim 19 , wherein a diameter of the solder ball or the solder pad is larger than a width of the corresponding passageway in the longitudinal direction.